I hope this helps you. I am not to sure what the standard is that you are refering to but from past experience with x-ray welding different interepters call things different. One may call it slag one may call it tungston, and if the shot was taken at an angle to make it look perfectly round they could call it porosity. Different places use different codes, a certain amount of porosity and suck back and so forth are allowable. Hope I helped you at all.